Use consistent bash5 style for conditionals and quoting

bin/omarchy-brightness-display

@@ -8,7 +8,7 @@ step="${1:-+5%}"
 # Start with the first possible output, then refine to the most likely given an order heuristic.
 device="$(ls -1 /sys/class/backlight 2>/dev/null | head -n1)"
 for candidate in amdgpu_bl* intel_backlight acpi_video*; do
-  if [[ -e "/sys/class/backlight/$candidate" ]]; then
+  if [[ -e /sys/class/backlight/$candidate ]]; then
     device="$candidate"
     break
   fi